The present disclosure relates generally to methods and apparatuses for detecting and identifying substances within a sample fluid. More particularly, the present invention relates to a portable, illustratively pocket wearable, laser based biosensor including modular components, and combining molecular absorption spectrophotometry and molecular fluorescence spectrophotometry.
Molecular absorption spectrophotometry (MAS) and molecular fluorescence spectrophotometry (MFS) are well established analytical techniques. More particularly, a variety of dedicated molecular absorption spectrophotometers and dedicated molecular fluorescence spectrophotometers are available from a variety of chemical instrument manufacturers. Some of these devices are portable. While simultaneous operation of MAS and MFS has been performed in research laboratories for solving specialized, fundamental problems; there are no known portable combination absorption-fluorescence spectrophotometers available in the market for the field testing of substances within a fluid sample.
There remains a need for the efficient field testing of substances within a fluid sample, combining both molecular absorption spectrophotometry (MAS) and molecular fluorescence spectrophotometry (MFS), in a single spectrophotometer, for performing both absorption and fluorescence measurements and providing rapid results to the user.
The present invention relates to a hand-held laser based biosensor that illustratively is portable (e.g., pocket wearable by a user), is modular (e.g., interchangeable modules), has improved selectivity (e.g., combined molecular absorption spectrophotometry and molecular fluorescence spectrophotometry), and has improved sensitivity (e.g., long absorption path length and long emission (fluorescence) region). Such a biosensor may find use in a variety of applications including, for example, in the military, food and drug industries, and with first responders (e.g., police and firefighters).
According to an illustrative embodiment of the present disclosure, a hand-held biosensor includes a radiation emitting module including light emitting module housing, and a light source received within the radiation emitting module housing and configured to generate excitation energy, illustratively a laser beam. The hand-held biosensor further includes a sample cell module including a sample cell module housing defining a chamber configured to receive a solution, a sample inlet in fluid communication with the chamber, and a waste outlet in fluid communication with the chamber. A first releasable coupling is positioned between the radiation emitting module and the sample cell module. An absorption detector is configured to detect emission intensity produced by the electromagnetic radiation passing through the solution in the sample cell chamber and produce absorption spectral data in response thereto, and produce absorption spectral data in response thereto, the absorption detector including an absorption detector spectral filter. A fluorescence detector is configured to detect molecular emissions produced by the laser excited molecules as the laser beam passes through the solution in the sample cell chamber and produces fluorescence spectral data in response thereto, the fluorescence detector including a fluorescence detector spectral filter. A processor is in electrical communication with the absorption detector and the fluorescence detector, the processor being configured to receive the absorption spectral data from the absorption detector and the fluorescence spectral data from the fluorescence detector. A display module is in electrical communication with the processor, the display module including a display module housing, an absorption display supported by the display module housing and configured to provide an indication of the absorption spectral data from the absorption detector, and a fluorescence display supported by the display module housing and configured to provide an indication of a fluorescence spectral data from the fluorescence detector. A power source is in communication with the processor. A second releasable coupling is positioned between the display module and the sample cell module.
According to another illustrative embodiment of the present disclosure, a hand-held biosensor includes an outer casing extending between a proximal end and a distal end, and a radiation emitting module supported proximate the proximal end of the outer casing. A display module is supported proximate the distal end of the outer casing, and the sample cell module is supported intermediate the radiation emitting module and the display module. The sample cell module includes a sample cell module housing defining a chamber and including a light entry port, a light exit port axially spaced by the chamber from the light entry port, a longitudinal axis defined by the light entry port and the light exit port, and a reflective surface configured to reflect light from the radiation emitting module transverse to the longitudinal axis. The hand-held biosensor further includes an absorption detector, a fluorescence detector, and a processor in electrical communication with the absorption detector and the fluorescence detector, the processor being configured to receive absorption spectral data from the absorption detector and fluorescence spectral data from the fluorescence detector. The sample cell module includes an axial length between the light entry port and the light exit port, the axial length being at least about 5 centimeters.
According to another illustrative embodiment of the present disclosure, a method of constructing a hand-held biosensor includes the steps of providing a sample cell module including a sample cell module housing having a side wall defining a chamber and extending longitudinally between a proximal end and a distal end, a sample inlet in communication with the chamber, and a waste outlet in communication with the chamber. The method further includes the steps of providing a solution within the chamber of the sample cell module, providing a radiation emitting module including a radiation emitting module housing extending longitudinally between the proximal end and the distal end, a light source received within the radiation emitting module housing and configured to generate an excitation laser beam, and releasably coupling the distal end of the radiation emitting module housing to the proximal end of the sample cell module housing. The method further includes the steps of providing an absorption detector at the distal end of the sample cell, the absorption detector configured to detect the intensity of the laser beam (energy) passing through the solution in the sample cell chamber, the absorption detector including an absorption detector spectral filter, and providing a fluorescence detector configured to detect emissions produced by laser excited molecules as the laser beam passes through the solution of the sample cell chamber, the fluorescence detector including a fluorescence detector spectral filter. The method also includes the steps of providing a processor in electrical communication with the absorption detector and the fluorescence detector, the processor configured to receive absorption spectral data from the absorption detector and fluorescence spectral data from the fluorescence detector. The method further includes the steps of providing a display module in electrical communication with the processor, the display module including the display module housing extending between a proximal end and a distal end, an absorption display supported by a display module housing and configured to provide an indication of the absorption spectral data, and a fluorescence display supported by the display module housing and configured to provide an indication of the fluorescence spectral data. The method further includes the steps of releasably coupling the distal end of the sample cell module housing to the proximal end of the display module housing, and providing a power source in electrical communication with the processor.
According to further illustrative embodiment of the present disclosure, a method of detecting a substance within a fluid sample using a hand-held biosensor includes the steps of providing a sample cell module including a sample cell module housing having a side wall defining a chamber and extending along a longitudinal axis between a proximal end and a distal end, a sample inlet in fluid communication with the chamber, and a waste outlet in fluid communication with the chamber, and fluidly coupling a waste collection vial to the waste outlet. The method further includes the steps of injecting a sample solution through the sample inlet into the chamber of the sample cell module, and generating an electromagnetic radiation with a laser light source. The method also includes the steps of directing the electromagnetic radiation through the sample solution in the chamber of the sample cell, absorbing the electromagnetic radiation by the sample solution, sensing the intensity of the electromagnetic radiation absorbed by the sample solution by an absorption detector, and generating an absorption signal of interest from the absorption detector. The method further includes the steps of producing fluorescence emissions from the sample solution, sensing the fluorescence emissions by a fluorescence detector, and generating a fluorescence signal of interest from the fluorescence detector. The method also includes steps of displaying an indication of the absorption signal of the absorption display, and displaying an indication of the fluorescence signal on the fluorescence display.
Additional features and advantages of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrative embodiments exemplifying the best modes of carrying out the invention as presently perceived.